Biomedical subjects

Seppo J Salminen

Publications and source records attributed to Seppo J Salminen.

7 recordsLinked to original sources

PubMed2006

Probiotic supplementation reduces a biomarker for increased risk of liver cancer in young men from Southern China.

BACKGROUND: In vitro and in vivo studies suggest that selected strains of probiotic bacteria can form tight complexes with aflatoxin B(1) and other carcinogens. OBJECTIVE: The aim of the present study was to determine whether administration of probiotic bacteria could block the intestinal absorption of aflatoxin B(1) and thereby lead to reduced urinary excretion of aflatoxin B(1)-N(7)-guanine (AFB-N(7)-guanine), a marker for a biologically effective dose of aflatoxin exposure. Elevated urinary excretion of this aflatoxin-DNA adduct is associated with an increased risk of liver cancer. DESIGN: Ninety healthy young men from Guangzhou, China, were randomly assigned to 2 groups; one group received a mixture of Lactobacillus rhamnosus LC705 and Propionibacterium freudenreichii subsp. shermanii strains 2 times/d for 5 wk, and the other group received a placebo preparation. The subjects provided 4 urine samples: at baseline, at 3 and 5 wk after starting the supplementation, and at the end of the 5-wk postintervention period. RESULTS: The percentage of samples with negative AFB-N(7)-guanine values tended to be higher in the probiotic group than in the placebo group during the 5-wk intervention period (odds ratio: 2.63, P = 0.052), and a statistically significant decrease in the concentration of urinary AFB-N(7)-guanine was observed in the probiotic group. The reduction was 36% at week 3 and 55% at week 5. The geometric means for the probiotic and placebo groups were 0.24 and 0.49 ng AFB-N(7)-guanine/mL, respectively, during the intervention period (P = 0.005). CONCLUSION: A probiotic supplement reduces the biologically effective dose of aflatoxin exposure and may thereby offer an effective dietary approach to decrease the risk of liver cancer.

Aflatoxin B1↗

PubMed2006

Intrinsic properties of so-called dormant probiotic bacteria, determined by flow cytometric viability assays.

Plate counting and four culture-independent flow cytometric assays were used to determine the viability and intrinsic properties of three probiotic strains during storage. The strains showed reduction in plate counts but were able to maintain esterase activity, intact cytoplasmic membrane, and pH gradient. The apparently uncultivable probiotic cells were active and stress resistant.

Animals↗

PubMed2005

Comparison of four methods to enumerate probiotic bifidobacteria in a fermented food product.

Four methods of enumeration were compared by monitoring levels of probiotic bifidobacteria in fermented oat drink during storage. Strains of Bifidobacterium longum and B. lactis were quantified by plate counts, fluorescent in situ hybridization (FISH), quantitative real-time PCR and commercial LIVE/DEAD BacLight bacterial viability kit, and the methods were further developed to suit the enumeration of bifidobacteria in fermented foods. Plate counts of both B. lactis and B. longum were lower than the PCR and FISH counts. The LIVE/DEAD counts of B. lactis were comparable to PCR and FISH counts. The plate counts of B. lactis were slightly but significantly lower than LIVE/DEAD counts, suggesting that the cells that were not able to grow on plates may have become dormant. The plate counts of B. longum were several log units lower than LIVE/DEAD counts, suggesting that a remarkable part of the cells were dormant. Real-time PCR and FISH were shown to suit the quantification of the total amount of probiotic bifidobacteria in foods. Plate counts and LIVE/DEAD counts provided conflicting information on viability especially in the case of B. longum. We conclude that the choice of enumeration method for probiotic bacteria may have significant effect on the results of the analysis. The strain-specific properties and the objects of the analysis should be taken into account when enumeration methods for different probiotic strains are chosen.

Bifidobacterium↗

PubMed2005

Similar bifidogenic effects of prebiotic-supplemented partially hydrolyzed infant formula and breastfeeding on infant gut microbiota.

The aim of the study was to assess the quantitative and qualitative differences of the gut microbiota in infants. We evaluated gut microbiota at the age of 6 months in 32 infants who were either exclusively breast-fed, formula-fed, nursed by a formula supplemented with prebiotics (a mixture of fructo- and galacto-oligosaccharides) or breast-fed by mothers who had been given probiotics. The Bifidobacterium, Bacteroides, Clostridium and Lactobacillus/Enterococcus microbiota were assessed by the fluorescence in situ hybridization, and Bifidobacterium species were further characterized by PCR. Total number of bifidobacteria was lower among the formula-fed group than in other groups (P=0.044). Total amounts of the other bacteria were comparable between the groups. The specific Bifidobacterium microbiota composition of the breast-fed infants was achieved in infants receiving prebiotic supplemented formula. This would suggest that early gut Bifidobacterium microbiota can be modified by special diets up to the age of 6 months.

Bacteroides↗

PubMed2005

Probiotics that modify disease risk.

Probiotics are defined as live bacterial preparations with clinically documented health effects in humans. Probiotics have specific properties and targets in the human intestinal tract and intestinal microbiota. Each probiotic strain, independent of its genus and species is unique and, thus, the properties and the human health effects of each strain have to be assessed in a case-by-case manner. Understanding the mechanisms by which probiotics influence the normal intestinal microbiota and counteract aberrancies in microbiota would facilitate the use of probiotics for both dietary management and reduction in risk of specific diseases. Development of intestinal microbiota is an important factor affecting the health of the newborn. Recent studies suggest that specific bacterial components, especially the bifidobacteria, have a key impact on development of a healthy balanced infant microbiota. The composition of infant and child intestinal microbiota may become aberrant and thus influence the development of diarrheal, inflammatory, and allergic diseases. Based on this understanding, positive health effects of probiotics have been reported in the management of diarrheal, inflammatory, and allergic diseases in infants. Most recently, a reduction in risk of atopic diseases followed early administration of specific probiotics.

Bacteria↗

PubMed2005

Probiotic bacteria may become dormant during storage.

The determination of bacterial viability in probiotic products is of economic, technological, and clinical significance. We compared four methods to enumerate three Bifidobacterium strains in fermented oat products during storage. A subpopulation of nonculturable cells retained a functional cell membrane typical of viable cells, indicating that probiotic bacteria become dormant during storage.

Avena↗

PubMed2003

Probiotic bacteria in the management of atopic disease: underscoring the importance of viability.

OBJECTIVES: The aim of this study was to assess the efficacy of oral supplementation of viable and heat-inactivated probiotic bacteria in the management of atopic disease and to observe their effects on the composition of the gut microbiota. METHODS: The study population included 35 infants with atopic eczema and allergy to cow's milk. At a mean age of 5.5 months, they were assigned in a randomized double-blind manner to receive either extensively hydrolyzed whey formula (placebo group) or the same formula supplemented with viable (viable LGG group) or heat-inactivated Lactobacillus GG (heat-inactivated LGG group), respectively. The changes in symptoms were assessed by the SCORAD method and the presence of some predominant bacterial genera in the feces detected with 16S rRNA-specific probes. RESULTS: The treatment with heat-inactivated LGG was associated with adverse gastrointestinal symptoms and diarrhea. Consequently, the recruitment of patients was stopped after the pilot phase. Within the study population, atopic eczema and subjective symptoms were significantly alleviated in all the groups; the SCORAD scores (interquartile range) decreased from 13 (range, 4-29) to 8 (range, 0-29) units in the placebo group, from 19 (range, 4-47) to 5 (range, 0-18) units in the viable LGG group, and from 15 (range, 0-29) to 7 (range, 0-26) units in the heat-inactivated LGG group. The decrease in the SCORAD scores within the viable LGG group tended to be greater than within the placebo group. The treatments did not appear to affect the bacterial numbers within the genera enumerated. CONCLUSIONS: Supplementation of infant formulas with viable but not heat-inactivated LGG is a potential approach for the management of atopic eczema and cow's milk allergy.

Administration, Oral↗